Liquid cooling moves onto the chip for denser electronics

Using microfluidic passages cut directly into the backsides of production field-programmable gate array (FPGA) devices, Georgia Institute of Technology researchers are putting liquid cooling right where it’s needed the most—a few hundred microns away from where the transistors are operating.

Combined with connection technology that operates through structures in the cooling passages, the new technologies could allow development of denser and more powerful integrated electronic systems that would no longer require heat sinks or cooling fans on top of the integrated circuits. Working with popular 28-nm FPGA devices made by Altera Corp., the researchers have demonstrated a monolithically-cooled chip that can operate at temperatures more than 60% below those of similar air-cooled chips.

In addition to more processing power, the lower temperatures can mean longer device life and less current leakage. The cooling comes from simple de-ionized water flowing through microfluidic passages that replace the massive air-cooled heat sinks normally placed on the backs of chips.

“We believe we have eliminated one of the major barriers to building high-performance systems that are more compact and energy efficient,” said Muhannad Bakir, an associate professor and ON Semiconductor Junior Professor in the Georgia Tech School of Electrical and Computer Engineering. “We have eliminated the heat sink atop the silicon die by moving liquid cooling just a few hundred microns away from the transistors. We believe that reliably integrating microfluidic cooling directly on the silicon will be a disruptive technology for a new generation of electronics.